Biomedical subjects

J J Adam

Publications and source records attributed to J J Adam.

4 recordsLinked to original sources

PubMed1992

Manipulating procedural variables in a spatial precuing task.

Spatial precuing tasks have yielded a consistent pattern of differential reaction time benefits. Specifically, precuing of two fingers on the same hand has been shown to result in faster discrete finger responses than precuing of two fingers on different hands. This phenomenon is called the hand advantage. Within the context of the spatial precuing task originally developed by Miller (1982), a series of four experiments investigated the influences of two procedural variables on the hand advantage: preparation instruction and presentation mode of preparation intervals. Two preparation instruction conditions were compared: implicit versus explicit instructions regarding preparation possibilities. Also, two presentation modes of preparation intervals were studied: a random condition, in which the preparation intervals varied randomly, and a blocked condition, in which the preparation intervals were grouped together in blocks of trials. Results showed that these two procedural variables, when manipulated independently, did not affect the hand advantage. However, when combined, they significantly reduced the hand advantage by half. Moreover, both procedural variables were shown to produce a precuing benefit for two homologous fingers on different hands. We concluded that, in spatial precuing tasks, procedural variables play an important role by inducing preparation strategies, which affect the pattern of reaction time benefits.

Choice Behavior↗

PubMed1992

Individual differences in visual information processing rate and the prediction of performance differences in team sports: a preliminary investigation.

This study used a backward-masking paradigm to examine individual differences in rate of visual information processing among university basketball, ice hockey and Canadian football players. Displays containing four letters were presented for stimulus durations ranging from 25 to 300 ms. Following stimulus offset, a masking stimulus was presented for 200 ms. The subjects were instructed to write down as many letters as possible from the briefly presented stimulus display on a specially prepared response grid. The results indicated consistent individual differences in rate of visual information processing. More importantly, it was found that rate of visual information processing as indexed by the backward-masking technique, has promising validity for predicting general performance excellence in university ice hockey and basketball players. Individual differences in rate of visual information processing were interpreted as reflecting the operation of attentional factors.

Adolescent↗

PubMed1991

Human information processing during physical exercise.

This study was designed to investigate how conditions of physical exercise affect human information processing. Sixteen subjects performed two information processing tasks (perception and decision) during two exercise conditions (endurance vs interval protocols) and during two control conditions (rest vs minimal load protocols). The control conditions required subjects either to perform the information processing tasks under resting conditions or while pedalling a bicycle ergometer at a minimal workload. Workload during the exercise protocols consisted of a fixed percentage of the subject's maximal workload. Each 40 min protocol consisted of five consecutive stages: practice, baseline, warming-up, exercise, and cooling-down, during which heart rate and ratings of perceived exertion were determined. In the perception task subjects had to identify a briefly presented row of three letters. In the decision task subjects had to indicate which of the outer numbers in a row of three digits was the larger. Results indicated that the two control protocols did not influence cognitive task performance; however, in the exercise protocols, increments in physical workload improved performance on the decision task and reduced performance on the perception task, while decrements in physical workload reduced performance on the decision task and improved performance on the perception task. Changes in mental task performance were not evident within protocol stages; only after stage transitions did changes in mental performance occur. We discussed possible theoretical approaches to explain these results and concluded that models advanced in the context of dual-task methodology seem most promising.

Adult↗

PubMed1991

Discrete finger response latencies in a simple reaction time task.

The present study evaluated the potential for neuroanatomical factors to operate in a simple reaction time task. That is, response latencies were recorded for all ten fingers on a Donders' A reaction time task. Two finger-placement conditions were used, a single response key condition and a multiple response key condition. This latter condition required subjects to place all ten fingers on response keys. 30 male, right-handed subjects participated. No significant effects were found, indicating that there are no intrinsically slow or fast fingers. This finding is discussed in the context of reaction time differences between individual stimulus-response (finger) pairs in choice-reaction time tasks.

Adult↗